M-矩阵逆矩阵的无穷大范数上界的进一步研究
2015-10-14黄卫华
周 平,黄卫华
-矩阵逆矩阵的无穷大范数上界的进一步研究
周 平,黄卫华
(文山学院数学学院,云南文山663000)
根据-矩阵的性质和无穷大范数的定义,得到严格对角占优-矩阵逆矩阵的无穷大范数上界的估计式,并给出-矩阵的最小特征值下界的新估计式. 理论分析和算例表明,文章给出的两个估计式改进了现有文献的估计算法.
-矩阵;对角占优;无穷大范数;最小特征值
1 基本定义和引理
定义2[1-7]若可表示为. 其中是单位矩阵,,是非负实数且,则称为-矩阵. 特别地,当时,称为奇异矩阵;当时,称为非奇异矩阵. 记所有阶非奇异矩阵所组成的集合为.
定义3[1]设的特征值为,令,则叫做的谱;中模最大的,即称为的谱半径.
定义4[3]设,记,称为的最小特征值且.
定义5[4-7]设,且满足条件:1),;2); 3),. 存在非零元素序列,其中,则称为弱链对角占优矩阵.
定义6[5]设,任取,有,则称为-矩阵. 设,非空指标集合,为行数和列数都是的的子矩阵. 令,其中. 例如表示删去的第一行第一列得到的矩阵.
定义7[5-6]设,若,则称为严格对角占优矩阵.
引理1[5]设是´阶弱链对角占优-矩阵,则也是弱链对角占优-矩阵,且存在,,.
引理3[7]设是严格对角占优-矩阵,,则.
引理4[4]设是´阶弱链对角占优-矩阵,,,,则,,,. 其中.
(2)
由式(1)和(2),得
.
.
,.
同理,根据定义4可得到下面的推论2.
注:由此推论可知,本文定理2改进了文献[6]中定理2的估计式.
.
3 算例
[1] 陈景良, 陈向晖. 特殊矩阵[M]. 北京: 清华大学出版社, 2001: 23-87.
[2] VARGA R S. On diagonal dominance arguments for bounding ||-1||¥[J]. Linear Algebra and its applications, 1976, 14(3): 211-217.
[3] CHENG G H, HUANG T Z. An upper bound for ||-1||¥of strictly diagonally dominant M-matrices[J]. Linear Algebra and its applications, 2007, 426(2-3): 667-673.
[4] SHIVAKUMAR P N, WILLIAMS J J, YE Q, et al. On two-sided bounds related to weakly diagonally dominant M-matrices with application to digital circuit dynamics[J]. SIAM Journal on Matrix Analysis and Applications, 1996, 17(2): 298-312.
[5] LI W. The infinity norm bound for the inverse of nonsingular diagonal dominant matrices[J]. Applications Math. Letter, 2007, 21(2): 258-263.
[6] HUANG T Z, ZHU Y. Estimation of ||-1||¥for weakly chained diagonally dominant M-matrices[J]. Linear Algebra and its applications, 2010, 432(2-3): 670-677.
[7] CHENG GUANGHUI, TAN QIN, WANG ZHUANDE. Some inequalities for the minimum eigenvalue of the Hadamard product of an M-matrix and its inverse[J]. Journal of Inequalities and Applications, 2013, 65(1): 1029-1035.
(责任编辑:饶 超)
Further Research on the Upper Bounds for the Infinity Norms of-matrices
ZHOU Ping, HUANG Weihua
(School of Mathematics, Wenshan University, Wenshan 663000, China)
According to the properties of-matrix and the definition of infinity norm, some upper bounds for strictly diagonally dominant-matrices are further researched, and the corresponding new results are given. At the same time new lower bounds on the smallest eigenvalue of-matrixis derived. Theory analysis and numerical figure showed that the theorem one and two in this paper improve the existing results in some cases.
-matrix; Diagonal dominance; Infinity norm; Minimum eigenvalue
O151.21
A
2095-4476(2015)05-0009-03
2014-12-15 ;
2015-01-08
云南省科技厅应用基础研究青年项目(2013FD052); 云南省教育厅项目(2013Y585); 文山学院重点学科数学建设项目(12WSXK01)
周 平(1987— ), 女, 云南永平人, 文山学院数学学院讲师.